Effects of touristic development on Mediterranean island wildlife

Abstract

Islands harbor unique and sensitive wildlife. Little is currently known, however, on how touristic development affects island species. We analyzed how tourism-associated infrastructure impacts wildlife and habitat availability across a representative Mediterranean island landscape (Naxos, Aegean Sea, Greece). First, we aimed to quantify how human-built structures (buildings and roads) affect island bird and reptile populations. Additionally, we investigated whether specific factors associated with this development such as cats, water, and food shape these impacts. Second, we mapped and quantified how touristic-dominated development over 33 years has changed landscape habitat availability for wildlife. We used wildlife field surveys and analyses to elucidate the spatial responses of wildlife to development, and combined this with a compilation of image-derived spatial data of the recent infrastructure expansion. Native birds declined strongly close to buildings and roads, and were replaced there by non-native invasive species. Reptiles also largely disappeared close to human development; appearing to be influenced by predation by pet cats. Over the study period, 1982–2015, human-built structures nearly doubled. Combining the increase in infrastructure numbers with each structure’s estimated ecological footprint, 100 m, revealed that only 20.5% of the potential wildlife habitat remains unaffected by development in the study region. This study demonstrates the landscape-level effects of diffuse tourism-dominated development on island wildlife and suggests the existence of cooperative effects between touristic expansion and exotic species. Given the pervasive presence of tourism in island habitats, it raises concerns about its effects on resident biodiversity.